Perhaps you should try some spelling variations:
hieu van » hieu va, thien van, lieu va
van tuan » van quan, van ban, anh tuan
hanh vai » hanh vi, hanh va, hanh tai
tu sach » thu sach, su sach, te sach
cao hoi » cau hoi, cao hoc, tao hoi
vai cua » dai cua, hai cua, lai cua
cua tre » cua te, cuu tre, cua triet
sach 2 » sach y
2 nang » v nang
co hoi » co hoc, co loi
luc va » tuc va, loc va

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sach 2 nang ((cao hoi) OR (co hoi)). hieu van tuan ((luc va) or (duc va)) hanh vai cua tre~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sach 2 nang ((cao hoi) OR (co hoi)). hieu van tuan ((luc va) OR (duc va)) hanh vai cua tre.
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sach 2 nang ((cao hoi) OR (co hoi)). hieu van tuan ((luc va) or (duc va)) hanh vai cua tre".
• Adding a wildcard symbol may retrieve word variants: tu sach 2 nang ((cao hoi) OR (co hoi)). hieu van tuan ((luc va) or (duc va)) hanh vai cua tre*.